5. Decision variables in supply chain modeling
In supply chain modeling, the performance
measures (such as those described in Section 4) are
expressed as functions of one or more decision
variables. These decision variables are then chosen
in such a way as to optimize one or more performance
measures. The decision variables used in the
reviewed models are described below.
f Production/distribution scheduling: Scheduling
the manufacturing and/or distribution.
f Inventory levels: Determining the amount and
location of every raw material, sub-assembly,
and final assembly storage.
f Number of stages (echelons): Determining the
number of stages (or echelons) that will comprise
the supply chain. This involves either increasing
or decreasing the chainÕs level of vertical